User Manual
Table Of Contents
- 1756-UM532A-EN-P
- Important User Information
- Table of Contents
- Purpose of This Manual
- Preface
- 1756-DH485 Module Overview
- Overview of the DH-485 Network
- Introduction
- DH-485 Network Description
- DH-485 Network Protocol
- DH-485 Token Rotation
- DH-485 Network Initialization
- Devices that Use the DH-485 Network
- 1747-AIC Isolated Link Coupler for DH-485
- 1761-NET-AIC Advanced Interface Converter Product Overview
- Operating Modes
- Device Compatibility
- Misconception about the 1761-NET-AIC Converter
- 1747-UIC USB to DH-485 Interface Converter
- Example System Configuration
- Important Planning Considerations
- Additional Resources
- Use Data Highway 485 Network
- Use RSLinx Software to Create a Routing Table
- Communicate from an SLC 5/03 Controller to a Logix Controller over a DH-485 Network
- Communicate Between SLC Controllers over DH+ and DH485 Networks
- Communicate Between a PLC-5 Controller and a Remote SLC 5/03 Controller over Multiple DH-485 Networks
- Communicate from an SLC 5/05 Controller to an SLC 5/03 Controller over an EtherNet/IP Network
- Communicate to a SLC 5/03 Controller on a DH-485 Network
- Communicate from a Logix Controller to an SLC 5/03 Controller over EtherNet/IP and DH-485 Networks
- Specifications
- Troubleshoot the 1756-DH485 Module
- Index
- How Are We Doing?
- Rockwell Automation Support
- Backcover
Publication 1756-UM532A-EN-P - May 2006
B-4 Troubleshoot the 1756-DH485 Module
Interpret the OK
Status Indicator
The three LED status indicators on the module provide information about
your module and the status of each channel. The following tables outline the
indicator condition and the corresponding status, and explain what each
condition means.
Interpreting the OK Status Indicator
Routing Errors in DH-485
Messaging
This section describes routing errors in local and remote messaging.
Routing Errors in Local DH-485 Messaging
If the 1756-DH485 module has a problem with routing a DH-485 message, it
may return a response with an error status of D0 hex. A PLC-5 controller
displays this error as D000 hex when monitoring the message instruction. If
you receive this error message, take the following actions:
• Check your message instruction to make sure a valid destination node
was entered.
• Check your default slot configuration to make sure that it matches the
location of the ControlLogix controller in the chassis.
• Make sure the 1756-DH485 module is turned on and verify chassis
power is recognized by the 1756-DH485 module.
If the Module OK
Indicator is
Module Status Recommended Action
Off Not operating. Apply chassis power.
V erify module is completely inserted into
chassis and backplane.
Red, then Off Performing self-test. None, normal operation.
Green Operating and routing
messages.
Verify module configuration.
Red In major fault Reboot module. If red reoccurs, then
replace module.